In The Sign of the Four, Sherlock Holmes and Dr. Watson are swept into a complex tale of betrayal, treasure, and revenge. The story begins when a young woman named Mary Morstan visits Holmes, seeking help to solve the mystery surrounding her father’s sudden disappearance years ago and the strange gifts of pearls she has been receiving annually from an unknown sender. Holmes, intrigued by the case, delves into a mystery that leads him and Watson deep into London’s dark alleys and across the globe to India, uncovering a hidden past of greed and vengeance. Along the way, Watson finds himself drawn to Mary, adding a personal layer to the case. The thrilling pursuit, exotic clues, and tense unraveling of a hidden treasure make this one of Holmes’s most suspenseful adventures.